The field of the disclosure relates generally to reciprocating systems and, more particularly, to a system for measuring conditions related to a piston rod.
Reciprocating systems typically include a reciprocating piston that moves axially within a cylinder and is either driven by or drives a piston rod coupled to the piston. Reciprocating systems include, for example, and without limitation, reciprocating engines, reciprocating gas compressors, integral reciprocating gas engine-compressors, i.e., motocompressors, and other reciprocating systems. In reciprocating compressors, the piston rod is coupled to a crankshaft such that rotational movement of the crankshaft, as powered by an engine or motor, is transformed into axial movement of the piston rod and piston coupled to the piston rod. The axial movement of the piston compresses gas within the cylinder. In reciprocating engines, a combustion chamber is in fluid communication with the piston and drives the piston. The piston is coupled to a piston rod moved axially by the piston. The piston rod is coupled to a crankshaft by a crosshead assembly and a connecting rod. Axial movement of the piston rod is transformed in rotational movement of the crankshaft by the geometry of the connection between the piston rod and the crankshaft provided by the connecting rod. As the piston rod experiences operational cycles fatigue loads, e.g., alternating or oscillation loads, occur in the piston rod which may result in outage of the reciprocating system. In the absence of a system to measure conditions related to the piston rod, outages of the reciprocating system may be unexpected and result in unplanned expense. Furthermore, in the absence of a system to directly measure conditions related to the piston rod, a reciprocating system cannot be accurately controlled to reduce fatigue loads or other loads on the piston rod. This limits the ability to increase the operational lifecycle of the reciprocating system and reduce unplanned outages through control of the operating conditions of the reciprocating system.